There must be something inspiring about dating a classical musician: Since private investigator
V.I. Warshawski took up with double bassist Jake Thibaut in
Hardball (2009), her creator, author Sara Paretsky, seems to have renewed creative
energy.

The considerable action of
Critical Mass (the title refers to nuclear physics) is set off when Warshawski is asked by
her friend Dr. Lotty Herschel to find Judy Binder, the daughter of Kitty, with whom Lotty grew up
in pre-World War II Vienna, and Judy’s son.

That assignment takes Warshawski from her Chicago neighborhood to a ruined downstate meth house
in a first chapter that contains some of Paretsky’s tautest writing ever. The narrative also moves
between wartime Vienna and present-day

Chicago, the misery of the Jewish ghetto and the luxuries of North Shore privilege.

It is a tale of intertwined generations. The miserable Kitty was the illegitimate daughter of
two nuclear physicists, sent from Vienna to Britain with Lotty and other Jewish children in the
Kindertransports in 1939. Her

mother, Martina, disappeared without a trace after a stint of slave labor. Kitty’s daughter,
Judy, is a drug addict, but Judy’s son, Martin, takes after Martina, a scientific genius. His
employer, a computer magnate, thinks that Martin is trying to sell company secrets.

Warshawski tracks down Judy, but Martin has “gone dark”; finding him takes most of the rest of
the book. She tangles with drug dealers and thugs, most notably a Bill of Rights-trampling pair
from the Department of Homeland Security, who wreck her office and apartment and shoot at her,
citing “an investigation connected to our national security” to justify anything they care to do.
Soon after, V.I. goes dark herself.

There is plenty of action, along with Paretsky’s usual dry humor.

With entombments, solved mysteries, loose ends neatly tied, good writing and a little bit of
love,
Critical Mass is a thoroughly satisfying read.